1. Field of the Invention
The invention relates generally to movable dam gates to forming a movable dam and particularly to a wicket gate operated hydraulically through a fixed strut.
2. Background of the Invention
Movable dam gates are common in the art and are utilized to maintain or regulate a pool of water upstream of a dam, such dam gates being raised to maintain maximum pool or lowered to pass maximum flows. Movable dam gates are also utilized to provide a navigable pass, gates adapted to this purpose often taking the form of wicket gates. Wicket gates which are generally available in the prior art must be lifted into position through utilization of a hoist mounted on a boat or bridge, the hoisting procedures used with such structure being slow and often unsafe. Hydraulically lifted wicket gates of the prior art have been driven through operating cylinders located in "wet" recesses. Hydraulic cylinders located in wet recesses are also subject to a more severe environment and are susceptible to sand and silt deposition on operating surfaces. Accordingly, prior hydraulically lifted wicket gates require maintenance and maintenance procedures must be conducted either in a "wet" environment or in a box structure within which the apparatus is dewatered. A need exists in the art for a movable dam gate and particularly for dam gates of the wicket type which are hydraulically operated both rapidly and safely. Further, a long-felt need exists in the art for hydraulically operated movable dam gates wherein the hydraulic apparatus associated with the gate can be maintained within an environment wherein siltation and other environmental factors do not require frequent and extensive maintenance and whereby required maintenance can be conducted within a dry environment without the need for extensive dewatering procedures. The disadvantages inherent in the prior art as noted above are obviated through a practice of the present invention which provides hydraulically operated movable dam gate structures operable both rapidly and safely and which require less frequent maintenance with such maintenance as is required taking place within a dry environment.